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Finding the Fourth Proportional to 279.39, 385.86 and 253.15

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Solution

The fourth proportional to 279.39, 385.86 and 253.15 is: 349.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.39 : 385.86 = 253.15 : x
  2. Step 2: Convert to fraction form
    279.39/385.86 = 253.15/x
  3. Step 3: Cross multiply
    279.39x = 385.86 × 253.15
  4. Step 4: Simplify right side
    279.39x = 97,680.46
  5. Step 5: Solve for x
    x = 97,680.46/279.39
  6. Step 6: Final answer
    x = 349.62

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.